For all the freedom he fought for, Lincoln was not one to let things like constitutional rights get in the way of fighting the Civil War.
This President Did the Unthinkable and Few Remember
Lincoln directed the violation of civil liberties to help the war effort.
Maryland was on the fence during the early days of the war, with citizens rioting and discussing leaving the Union. Lincoln put a stop to this by suspending the writ of habeus corpus, and sending agents to imprison anyone they saw fit, without a trial, for any period of time.
This included newspapers and their writers and publishers. 13,000 citizens would be jailed, even though the courts ruled that Lincoln had violated the Constitution.
Source – https://www.heritage.org/research/lecture/abraham-lincoln-and-civil-liberties-in-wartime
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